Spellshock

Whenever a player casts a spell, Spellshock deals 2 damage to that player.

Ruby Medallion

Red spells you cast cost {1} less to cast.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Rampaging Ferocidon

Menace
Players can't gain life.
Whenever another creature enters, Rampaging Ferocidon deals 1 damage to that creature's controller.

Ankh of Mishra

Whenever a land enters, Ankh of Mishra deals 2 damage to that land's controller.

Coldsteel Heart

Coldsteel Heart enters tapped.
As Coldsteel Heart enters, choose a color.
{T}: Add one mana of the chosen color.

Zo-Zu the Punisher

Whenever a land enters, Zo-Zu the Punisher deals 2 damage to that land's controller.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Mountain

Temple of Power

(Transforms from Ojer Axonil, Deepest Might.)
{T}: Add {R}.
{2}{R}, {T}: Transform Temple of Power. Activate only if red sources you controlled dealt 4 or more noncombat damage this turn and only as a sorcery.

Ojer Axonil, Deepest Might

Trample
If a red source you control would deal an amount of noncombat damage less than Ojer Axonil's power to an opponent, that source deals damage equal to Ojer Axonil's power instead.
When Ojer Axonil dies, return it to the battlefield tapped and transformed under its owner's control.

Ojer Axonil, Deepest Might // Temple of Power

Manabarbs

Whenever a player taps a land for mana, Manabarbs deals 1 damage to that player.

Liquimetal Torque

{T}: Add {C}.
{T}: Target nonland permanent becomes an artifact in addition to its other types until end of turn.